Homogenization near resonances and artificial magnetism from dielectrics

The homogenization of periodic dielectric structures in harmonic regime usually leads to an effective permittivity tensor epsilon(eff). It has been observed by Bouchitte and Felbacq [Waves Random Media 7 (1997) 245-256], that in the high contrast case (high conductivity fibers), this tenser depends on the angular frequency omega. In this Note, we enlight a new effect induced by microscopic resonances which leads in parallel to a possibly negative effective permeability mu(eff)(omega) (although the original medium is assumed to be nonmagnetic i.e. mu = 1). (C) 2004 Academie des sciences. Published by Elsevier SAS. All rights reserved.